Inclosed switch



June 14, 1932. H. J. HAMMERLY INCLOSED SWITCH 2 Sheets-Sheet 2 FiledNov. 14, 1930 INVENTOR Patented June I4, 1932 UNITED STATES PATENTOFFICE HERMAN J". HAMMERLY, OF WALLINGFORD, CONNECTICUT, ASSIGNOR TO THETRUM- BULL ELECTRIC MANUFACTURING COMPANY, OF PLAINVILLE, CONNECTICUT, A

CORPORATION OF CONNECTICUT INCLOSED SWITCH Application filed November14, 1930. Serial No. 495,600.

type and are caused to move in a relatively perpendicular direction withrespect to the plane of the enclosing box.

In switches of this class, the blades are usually mounted on, andmovable with some kind of a guiding slide, or an equivalent of a slide,and the necessary length of such slides, plus the operating movement ofthe slides, plus the necessary separation of the respective contactswhen in the off position, or-

16 dinarily necessitates a relatively deep box or enclosure for theswitch.

Applicants co-pending application Ser. No. 335,250, filed January 26,1929, now Patout No. 1,838,020 shows a form of switch in which pivotedknife switch blades are employed and in which the operating crank ispivoted in the opposite side walls of the box with an intermediateoperating member and an external operatinghandle mounted concentricallywith one end of the crank.

In the form shown in this co-pending application, the pivot centers ofthe co-related operating members are spaced in the side wall of the boxat a point high enough from the bottom of the box to'provide for amplemounting and operating space for sturdy and well proportioned operatingparts.

Applicants present invention involves the problem that the switch blademovement is straight in and straight out rather than in the arcuatedirection of a hinged or pivoted blade and in meeting the requirement ofa shallow box, it will readily be seen that, in one of its positions,the bail portion of the operating crank will stop at a point so veryclose to the bottom of the box and the crank must be pivoted at a pointso low in the box thatit would be a very diflicult problem to provideco-operating means for engaging the crank in the usual manner or tomount the co-operating means on the same pivot center line as the crankmember.

, Applicant has solved the problem by providing a special crank whichhas one of its ends pivoted in one side wall of the box and its otherend pivoted in a special angle plate secured to the bottom of the boxand has an angularly bent end extending through the angle plate forengagement with the projecting lugs of an intermediate member which, inturn, is engaged by the external handle with a lost motion connection.

Applicants intermediate member and the external handle are co-axiallymounted on the side wall of the box, with their axial centers positionedat a point a considerable distance away from the axial center of thecrank mounting.

It will be noted that the axial centers of the intermediate member andof the external handle are spaced so far away from the axial center ofthe crank member that ample space is provided on the inner wall of thebox, for making the intermediate member of very substantial proportionsand this eccentric arrangement of mount-in the respective corelatedoperating mem ers provides open space for ample operating range ofmovement for the switch throwing spring.

By reason of the crank and the intermediate member being pivoted atdifferent axial centers, the lugs on the intermediate member will engagethe projecting end of the crank with a sliding or cam-like movementwhich exerts a very easy but powerful force against the crank in itsinitial movement towards the position where the spring will force itrapidly away from the lugs of the intermediate memher to the fully openor fully closed position.

Some of these features altho especially adapted to the actuation of thesliding type of contact will be found useful for other types.

Fig. 3 is a side view and partial section q showing the actuatingmechanism with the a parts in the positions they occupy in the opencircuit condition.

Fig. 4; is a similar view showing the parts in the closed circuitposition.

Fi 5 is an exploded perspective view showing parts of the actuatingmechanism.

The box 7 has a cover hinged at 8 and provided with a latch 10 in thecustomary manner.

The conducting parts of the switch are car'- ried by an insulating block11 suitably secured in the box, for instance, by screws 12.

The invention is applicable to the control of a circuit having anyreasonable number of poles and I have illustrated it as applied to aswitch for a three wire system. All of the switch units being the sameit is only necessary to note that each unit has contacts 14 and 15 withcircuit terminals of a. suitable character and a movable switch contactmember 16 mounted to slide in the base or block 11. In this form themovable switch contact is U-shaped and supported by a sliding carrier 17as is more fully set forth in my c0- pending application Ser. No.469,152, filed July 19, 1930, now Patent No. 1,824,137.

The operating crank shaft 18 is pivoted at 19 in one side of the box andpivoted at 20 1n an angle plate 21 which is secured to the bottom of thebox. The crank shaft is loosely connected with the sliding carrier 17 inany suitable manner so that as the crank shaft is swung on its pivotedends 19 and 20 the carrier 17 is made to slide and bring the switchmember 16 into contact with and out of contact from the stationaryswitch contacts.

The handle 22 is mounted on a sleeve or bushing 23 which extends throughthe open ing 24 in the side of the box. A bracket 25 secured to theoutside of the box serves as a stop and has convenient means for lockingthe handle in the open or closed circuit position by means of a padlockor sealing wire (not shown) of the usual character.

This handle 22 carries a stud or pin 26 which projects through a curvedslot 27 in the side of the box.

Inside the box a connector disc or intermediate member 28 is mounted onthe sleeve 23 and provided with a cut-out portion bounded by shoulders29 and 30 with which the pin or stud 26 is adapted to coact. A disc 22is also preferably provided on the sleeve 23 between the handle and theside of the box to close the slot 27 The connector 28 is also providedwith lugs 31 and 32 which project inwardly from the side of the box onopposite sides of the crank arm. 33.

In order to insure a quick break or snap action, I provide the connector28 with a projecting arm35 to which is pivoted or hinged one end of thebar' 36 the other end of which is ided in a bracket 37 secured to theinner we. 1 of the box. A spring 38 is mounted on this rod 36 and tendsto move the disc 28 to the one or the other of the two positions shownin Figures 3 and 4, as is customary in actions of this character.-

To operate the switchfrom the open to the closed circuit position, thehandle 22 is raised until the pin 26 engages the shoulder 30 on theconnector disc. Continued movement of the handle upwardly rotates thedisc 28 about the sleeve 23 and thus compresses the spring 38 until itsconnection with the rod 36 passes the center line between the axis ofthe bearing sleeve 23 and the bracket 37 In the meantime the lug 32 haspicked up the crank arm 33 so that the spring throws the connector andthe crank arm into the position shown in Fig. 4.

1 This movement of the crank arm and shaft throws the movable switchmember to the closed circuit position. To open the circuit the handle 22is returned to its original position during which movement the pin 26en.- gages the shoulder 29 on the connector 28 and the connector isrotated until the lug 31 engages the crank arm 33 and forcibly starts tomove the crank shaft and movable switch member toward the open circuitposition which action is completed with a quick break by the pressure ofthe spring 38. It will be seen that on account of the fact that thecrank shaft bearing 20 is considerably eccentric with respect to theconnector disc 28, that the lug 31 first engages the crank arm 33 nearthe point 40 and then slides along the crank,

arm outwardly toward the end producing an effective snap action. I

It will be noted that the box is so constructed and arranged that theycan be assembled and tested in units before complete assembly. Forinstance, the insulating block carries the stationary as well as themovable contacts, the box carries the handle and quick make and break orsnap action mechanism and the crank shaft is supported in the box andinthe angle plate 21 independently of the snap action mechanism.

The advantages of my construction will be apparent from an inspection ofFigs. 2, 3, 4 and 5 of the drawings.

It will be noted that the intermediate disc or operating member 28 is ofvery substantial proportions. This is made possible by the fact that theaxial center of the disc is positioned at a considerable distance fromthe axial center of the crank shaft, in other words I the axial centerof the disc is considerably higher from the bottom of the box than theaxis of the crank shaft and is offset in tangential relation to theaxial center of the crank shaft.

In some structures it has been the general practice to eo-axially mountthe switch crank and its co-related operating means but, in order tomount applicants disc 28 co-axially with the crank shaft, the disc wouldhave to end 33 of the crank 18 with a wiping or cam action which addsmaterially to the smooth operation of the switch.

It will also be apparent from the drawings that, in order to obtain adesirable corelation of the quick break mechanism members, it was founddesirable to form one end of the crank shaft with a special projectingend-33 and to provide a special bearing for that end of the crankinsideof the box as shown in the drawings of members 21.

As the support for the crank shaft member is independent of the sideplate which supports the handle and snap action device it is obviousthat considerable bending or displacement of the side plate might occurwithout crippling the switch mechanismin fact the side plate andattached parts might be removed without disturbing the switch contactsand operating crank.

I claim:

1. In a switch a box, a switch member slidably supported in said box, acrank shaft pivotally supported in the box for moving said switch memberand having a projecting arm inside of the box, an operating handlepivoted to one side of the box, a connector pivoted inside of said boxand having a lost motion connection with said handle and with said crankarm, said connector being mounted eccentric to the axis of the crankshaft and said connector having projectin lugs for a sliding engagementwith the sai projecting arm of the crank shaft.

2. In an electric switch, a stationary con tact, a movable switchmember, a pivoted crank shaft for actuating said movable switch memberand having an arm, a pivoted operating handle and an oscillating lostmotion connector mounted to oscillate about an axis, which issubstantially eccentric to the axis of said crank shaft, said connectorbeing actuated by said handle and being provided with projecting armsadapted for a sliding engagement with the arm of said crank shaft toactuate said movable switch member.

3. In a switch, a stationary contact, a slidable switch member coactingtherewith, a pivoted crank shaft for actuating said switch member, andhaving a projecting arm, an

oscillating connector disc having lugs spaced apart from each other andhaving a sliding engagement; with the projecting armof said crank shafton opposite sides of said crank arm, an operating handle having a lostmotion connection with said connector disc and a spring device coactingwith one of said members for actuating said switch member with a snapaction. The said oscillating disc being pivotally mounted with its axialcenter spaced away from the axial center of said crank shaft for thepurpose set forth.

4. In an electric switch, a stationary contact, a movable switch memberhaving a contact to coact therewith, a pivoted crank shaft for actuatingsaid movable switch member, a pivoted operating handle and anoscillating connector mounted to oscillate about an axis substantiallyeccentric to the axis of said crank shaft, said connector being actuatedby said handle and in turn serving to engage a portion of said crankshaft with a cam action and actuate said crank shaft, and a springdevice for actuating said switch member with a snap action.

5. In an electric switch, a box, an insulating base mounted therein,stationary and movable contacts carried by said base, a plate secured inthe box between the base and one side of the box, an operating crankshaft having one of its ends pivoted in oneside of the box and its otherend pivoted in said plate and having a projecting crank arm, anoscillating disc pivoted in one side of the box and having a slidinglost motion connection with said crank arm, a throwing spring for saiddisc and an operating handle pivoted in one side of the box and having alost motion connection with said disc.

' 6. In an electric switch, a box, an insulating base mountedtherein,stationary and movable contacts carried by said base, a platese-' cured in the box between the base and one side of the box, anoperating crank shaft having one of its ends pivoted in one side of thebox and its other end pivoted in said plateand having a projecting crankarm, an oscillating disc pivoted in one side, of the box and having asliding lost motion connection with said crank arm and an operatinghandle pivoted in an adjacent side of the box and having a lost motionconnection with said disc and a throwing spring for said oscillatingdisc, the axis of the disc being substantially eccentric with respect tothe axis of said crank shaft.

7. An electrioswitch including a box, an insulating base within the box,stationary and movable contacts supported by said base, a crankpivotally mounted within said box, an external operating handle, anintermediate member having a lost motion connection with said externalhandle and a sliding engagement with a portion of said crank and aspring for accelerating the operating movement of said intermediatemember, the said intermediate member being pivotally mounted with itsaxial center spaced definitely away from the axial center of said crankfor thepurpose specified.

8. An electric switch including a box, an insulating base in said box,stationary contacts on said base, a movable switch member slidablysupported by said base, a crank shaft pivotally supported in said boxfor operating said movable switch member and having 5 a projecting arm,an external operating handle pivoted to said box, an operating connectorin said box and having a lost motion connection with said externalhandle and a sliding lost motion engagement with the projecting arm ofthe said crank and a spring for rapidly throwing said crank, the saidconnector being pivotally mounted in the side of the box at a pointrelatively' remote from the axial center of said crank.

, I 9. An electric switch including a box, a base within the box,stationary and movable contacts supported by said base, a crankpivotally mounted in said box and having operable connection with saidmovable contacts,

to an external operating handle, an intermediate member having a coaxiallost motion connection with said external handle and an eccentric lostmotion sliding engagement i v with said crank, a quick motion springhaving operable connection with said intermediate member the saidintermediate member being pivotally mounted in said box with V its axialcenter spaced away from the axial center of the crank shaft in themanner speci- 10. In an electric switch, a box, an insulating basemounted therein, stationary and movable contacts carried by said base, aplate secured in the box between the base and one :-:5 side of the box,an operating crank shaft pivoted in the opposite side of the box and insaid plate and having a projecting arm inside of said box, anoscillating disc pivoted in an adjacent side of the box and having 40 asliding lost motion connection with the projecting arm of said crank andan operating handle pivoted in an adjacent side of the box and having alost motion connection with said disc and a throwing member connectingsaid disc to said box.

HERMAN J. HAMMERLY.

